feat(github-release): update fluxcd/flux2 to v2.7.1

Author: renovate[bot]

kubernetes/base/flux-system/bootstrap/kustomization.yaml

@@ -17,7 +17,7 @@
 apiVersion: kustomize.config.k8s.io/v1beta1
 kind: Kustomization
 resources:
-- github.com/fluxcd/flux2/manifests/install?ref=v2.6.1
+- github.com/fluxcd/flux2/manifests/install?ref=v2.7.1
 patches:
 - patch: |-
     $patch: delete